Negative Dielectric Anisotropy Liquid Crystal Composition for Fast Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing liquid crystal compositions for active matrix devices lack a balance of high maximum and low minimum nematic phase temperatures, small viscosity, large negative dielectric anisotropy, and high stability to ultraviolet light and heat, which affects the devices' response time, voltage holding ratio, and service life.
Innovation Solution
A liquid crystal composition with negative dielectric anisotropy, comprising specific compounds represented by formulas (1) and (2), optimized with specific ratios of components to achieve desired properties, including a wide temperature range, low viscosity, and high stability, suitable for various operating modes like VA, IPS, and FFS.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a liquid crystal composition is designed to have a wide temperature range of nematic phase, then the usable temperature range is improved, but the viscosity may increase and response time deteriorates
Solution Approach 1:
The patent applies parameter changes by carefully selecting and adjusting the chemical structure parameters of liquid crystal molecules (including molecular weight, structural groups, and composition ratios) to achieve an optimal balance between temperature range and viscosity. By modifying molecular parameters such as the introduction of specific functional groups and adjusting the ratio of different components, the composition achieves wide temperature operation while maintaining acceptable response time performance.
2Speed
If the viscosity of the composition is reduced to achieve short response time, then the response time is improved, but the stability to ultraviolet light and heat may deteriorate
Solution Approach 1:
The patent employs composite materials by combining multiple liquid crystal components with different molecular structures and properties. This composite approach allows the composition to integrate the low viscosity characteristics needed for fast response time with the high stability characteristics required for long service life. The synergistic effect of multiple components enables simultaneous optimization of both response time and stability to ultraviolet light and heat.
3Use of energy by moving object
If the dielectric anisotropy is increased to achieve low threshold voltage and small power consumption, then the voltage holding ratio is improved, but the optical anisotropy may be affected
Solution Approach 1:
The patent applies parameter changes by adjusting the dielectric anisotropy parameter through selective combination of liquid crystal components with specific molecular structures. By optimizing the composition ratios and molecular parameters, the patent achieves high dielectric anisotropy for low power consumption while maintaining acceptable optical anisotropy for adequate contrast ratio performance in the liquid crystal display device.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The composition provides a liquid crystal display device with a short response time, large voltage holding ratio, high contrast ratio, and long service life, suitable for applications in liquid crystal projectors and televisions.
Implementation Method 1
a liquid crystal composition having a negative dielectric anisotropy
Implementation Method 2
An optical anisotropy of the composition relates to a contrast ratio in the device
Data Source
AI summary
To provide a liquid crystal composition satisfying at least one characteristic including a high maximum temperature of a nematic phase, a low minimum temperature thereof, a small viscosity, a large optical anisotropy, dielectric anisotropy and specific resistance, a high stability to ultraviolet light and heat, or a liquid crystal composition having a suitable balance regarding at least two characteristics; and an AM device having a short response time, a large voltage holding ratio and contrast ratio and a long life; a liquid crystal composition has a negative dielectric anisotropy and contains a compound having a low minimum temperature as a first component and a compound having a large negative dielectric anisotropy as a second component, and may contain a compound having a small viscosity as a third component and a compound having a large negative dielectric anisotropy as a fourth component, and a liquid crystal display device containing the composition.